The Oyster Project is dedicated to oyster restoration in the estuaries of Massachusetts. Oyster reefs provide shelter for 100 other species including shrimp, eels, lobsters and the young of many commercial species. Oysters also are tremendous water cleaners as each filters 30 gallons of water per day.

Saturday, December 10, 2016

Oysters Improving Water Quality at Cape Town

We recently learned of this exciting effort to use oysters to reduce nitrogen loads in a Cape Cod town's waters. This is an approach we have been advocating for some time as it offers an environmentally friendly way to reduce nitrogen. Importantly, the oysters are most active in the summer time when the population is highest. It will be exciting to see the result.

Oysters wintering in Lonnie's Pond as pilot program continues

By Doreen Leggett

dleggett@wickedlocal.com

The surface
of Lonnie's Pond will soon look as smooth as slate-colored silk; the 200,000
oysters that floated on the surface of the water in bags all summer will be
replaced with occasional reflections of the bronze-leaved trees on the shore.

Now the
waiting begins. The oysters, which will be placed on the bottom of the pond by
researchers, will lay virtually dormant until March when they will begin once
again to devour the nitrogen that helps turn the once-clear pond into a murky
green.

But for
those on land the end of January is a more significant date. That is when
scientists from various institutions, including UMASS's School of Marine
Technology, will have crunched the numbers and filed a report that could change
the future of wastewater management in Orleans.

If the
oysters have removed enough nitrogen then the second phase of the pilot project
will begin and several other projects in town, which have aquaculture at the
center of pollution abatement, will likely move forward.

"What we
want to get to is: What is the cost per pound of nitrogen removed?"
Selectman Alan McClennen said.

Close to 300
kilograms - 630 pounds - of nitrogen a year need to be removed to meet the
state-mandated total maximum daily load limit. If the oyster project shows that
oysters can make a difference, at a low cost, the town will move into the next
phase.

The second
installment of oysters in the pond could reach 1 million animals and the
numbers from that pilot, along with the work done this summer, would be used to
help convince state regulators from the Department of Environmental Protection,
to let Orleans skip pipes in the ground - at least on Kescayoganset and nearby
roads.

"The
existing comprehensive wastewater management plan says we are going to sewer
Lonnie's Pond, we are trying to avoid that," said McClennen at a recent
meeting of the Orleans Water Quality Advisory Panel.

Although
it's hard to run the numbers, particularly since the oyster pilot program is
still ongoing, 7-year old Autumn, who has been at the pond frequently with this
reporter, thought $500,000 to remove nitrogen, compared to millions for even a
small sewer system seemed to make sense, particularly since it can cost up to
$600 per pound for small sewer plants to remove nitrogen. She is willing to bet
on the bivalve for the moment.

There are
some questions over whether the oysters are going to be enough - some have said
it would be cheaper and easier to just remove the sediment at the mouth of the
pond to improve tidal flushing, and thereby water quality. There are also
questions about what the next phase will look like - the initial work relied on
larger than typical oysters from Falmouth, volunteer work, consultants, and
paid local shellfish growers. In the future the project may be done with town
staff, by private growers, or some other scenario.

Although
questions remain, what is clear, said Sia Karplus, of Sciencewares, which is in
charge of the project for the town, is the oysters are growing well. Oysters
that arrived as the size of a cornflake are now well on their way to the size
of a flattened mini muffin and those that were thumb-sized look more like a
fist.

Eric
Karplus, also of Sciencewares, was down at the 15-acre pond late last month, on
an unseasonably warm - albeit still raw - day. He, as he did once a week, with
the help of growers from Peter Orcutt's Pleasant Bay Oyster Farm, had taken
some oysters from the 800-bag raft in order to weigh and measure them.

"These
guys are growing like gangbusters," he said. "We came in with a few
thousand pounds and now we have 10 tons of oysters out there."

Karplus said
that amount of growth isn't typical, but there is a lot of food out there for
them to eat. Part of the reason for the buffet is because the pond is one of
the most impaired in town - like ponds all over the Cape it is suffering from
nitrogen pollution coming mainly from septic systems.

Since the
growing season had ended, this was the last day Karplus would be taking stats
at a makeshift table by the shore. He was already in the process of putting the
oysters on the bottom of the pond, in a contraption that will keep them off the
mucky bottom, for the winter.

"It is
really important to store them in a way that they continue to feed,"
Karplus said. If the oysters were smaller they could have been taken out of the
pond to overwinter in a storage facility, but with larger oysters he said the
chance of mortality was too great.

The reams of
water quality data collected from several long-standing sampling stations, and
also gathered from instrumentation set in the pond by SMAST will be correlated
with the information gathered from oyster measurements that Sciencewares has
taken.

But as
Karplus tipped over a bucket of oysters and saw the size of the shellfish
tumbling out he was encouraged.

"The
only way the oyster grows is they are taking nitrogen out of the pond," he
said.

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About the Mass Oyster Project for Clean Water

MOP is a 501c-3 non-profit dedicated to restoring water-cleansing oysters to Boston Harbor after their being absent for decades. Each oyster can filter 30 gallons of water per day. An oyster reef can shelter up to 100 other species so they dramatically add to biodiversity. Oysters also sequester nitrogen in wastewater and each person creates 12 pounds per year. Oyster shells contain calcium carbonate a known buffer that can help offset ocean acidification. MOP has shown that oysters can survive and grow in Boston Harbor. The group is now seeking to optimize placements to maximize survival and eventually show reproduction. Come join us in making your Harbor healthier!